File content as of revision 0:b191e77dc856:

#include "mbed.h"


SPI spi(p11, p12, p13); // mosi, miso, sclk
DigitalOut cs(p14);

Serial pc(USBTX, USBRX); // tx, rx

// Not possible to use inline assembler language with this device, error 1044
/*#pragma arm
void NOP()
{
  
  __asm                    
  {
    NOP
  }
}
#pragma thumb*/





int main() {
    // Setup the spi for 8 bit data, high steady state clock,
    // second edge capture, with a 1MHz clock rate
    spi.format(8,0);
    spi.frequency(1000000);
    int teste, result, b=0;
    
       
    teste=0xAA;
    
    cs=0;
    pc.printf("Answer before = %d\n\r", teste);
    
    
    spi.write(teste);  
        
    cs=1;  // it's necessary to close and open the connection for the program to work, we believe that's necessary to exchange the buffer values 
            // not exactly sure how much must this delay be
    
    if(b<1){} //  delay necessary between closing and opening a connection with the slave, we believe it's because of the high clock value of the mbed
    
    
    
    cs=0;
    result=spi.write(0x00); // to read the value of the previous reply from the slave, it's necessary to make another write sending a dummy byte
    cs=1;   
    
    
    pc.printf("Answer later= 0x%X\n\r", result);   
    // Maybe what is happening is that we need a bigger delay between the two writes so that it works the first time,maybe result is showing not the
    //value of the previous write in this run of the program, but the value stored in the buffer in the previous run
     
        

    
}